1. Field of the Invention
The present invention is directed to video adapters with or without one or more television tuners, which adapters are capable of supporting multiple television type monitors, and software for controlling the same. These documents are incorporated herein by this reference. The present invention is directed to video adapters with or without one or more television tuners, which adapters are capable of supporting multiple television type monitors, and software for controlling the same.
2. Background
Video adapters (or xe2x80x9cvideo cardsxe2x80x9d) convert computer data to video signals for output to a monitor or similar output device. A typical Video Graphics Array (xe2x80x9cVGAxe2x80x9d) card has its own memory and digital-to-analog converter (xe2x80x9cDACxe2x80x9d), but does not actually process data, which is performed by the computer""s CPU, including writing and reading of text, as well as drawing simple graphics primitives such as pixels, lines and memory transfers for images.
Programs such as DOS-based word processors run in VGA text mode while graphics-based programs such as games run in graphics mode. The operating systems sold under the trademark Windows by Microsoft Corp. run in VGA graphics mode as default, meaning that every pixel that is displayed as a part of the background, a window, or a text character must be written using basic VGA calls. The low-level nature of the VGA command set dictates that numerous commands be required to do something as simple as moving or closing a window. Clearly, an enormous amount of data is required to move from the VGA card, along the bus, into the CPU, and on into the card""s memory, and vice-versa.
Accelerated video cards, however, have their own processor (or xe2x80x9cacceleratorxe2x80x9d). Thus, an accelerated card may perform many video operations with only minimal input from the CPU. Indeed, the accelerated video card can perform all of the operations usually performed by the CPU with a VGA card. This frees the bus and the CPU to execute other tasks, and speeds-up video operation. Unlike VGA mode, where every pixel must be moved to and from the card via the bus and CPU, the accelerated card can perform the same operations with instructions consisting of only a few bytes being transferred along the bus. This results in an enormous performance gain for most common graphics operations, including bitmap and pixmap transfers and painting, movement of sprites and icons, opening and closing of windows, etc.
The increased performance of accelerated cards has permitted the introduction of more advanced graphics features. For instance, certain advanced accelerated cards now feature television tuning capabilities. Television cards include a television tuner capable of receiving and tuning a video source from a cable or a video cassette recorder. The card then converts the incoming video source into a signal that may be displayed on a conventional computer monitor. Cards with television tuners typically have additional processing and memory requirements.
Currently, adapters or external devices (so-called xe2x80x9cTV Out devicesxe2x80x9d) are available which contain encoders or other circuitry to convert VGA video signals to composite or S-Video television signals. This allows computer screens of information to be viewed on a television monitor. Such devices thus leverage on the fact that a television set has a lower cost than a computer monitor.
Current users combine multiple single video adapters and multiple TV Out devices into a system in order to create a xe2x80x9cvideo wallxe2x80x9d. A video wall is an array of television sets or monitors that can display a number of individual video programs, or one or more video programs, over an entire array of television monitors. Currently, a system formed of many single video adapters and many single TV Out devices requires complex cabling and large systems to support the video wall. Controlling the devices in order to determine what programming appears on what television monitor, as well as the manner in which such programming appears, presents another formidable set of issues.
The present invention provides devices, systems and processes for displaying programming, which can include one or more programs or groups of content originated on a computer, on multiple television monitors. Video adapter hardware of the preferred embodiment of the present invention includes at least one user interface or graphics accelerator. Each accelerator can be coupled to an independent memory unit and a shared memory unit. The adapter can communicate with the computer""s main CPU such as via the internal bus or bus interface. A bus bridge can handle data flow and concurrency issues if needed. Thus, the accelerator or accelerators can coordinate with the computer, process information from the computer, and otherwise do the necessary to render information from the computer in suitable form and/or format, via current standards or via any future standards, for presentation or display.
Adapters according to the present invention also include at least one TV out functionality which may be of conventional design or as otherwise desired. This functionality accepts output from the accelerator or accelerators and processes such output for display on television monitors (as differentiated from, for example, computer monitors). The aim is to display computer originated or generated information on a television monitor in order to leverage the lower cost of television monitors and the many other advantages to be gained from displaying information or content on such monitors.
According to a first embodiment of the present invention, accelerator functionality may be combined with TV out functionality to feed video multiplexer functionality which in turn supports two or more television monitors. A variant of this embodiment supports four television monitors.
According to a second embodiment of the present invention, two or more accelerator functionalities may be combined with two or more TV out functionalities to support two or more television monitors. In a variant of this embodiment, the TV out functionalities feed video multiplexer functionality to support four television monitors.
Adapters according to the present invention offer a number of useful and desirable results. Consider, for example, supporting a video wall. Video walls usually require a large number of television monitors to display one program or multiple programs. Previously, such walls were supported by an array of graphics accelerator cards, each of which was connected to a TV out card, each of which TV out cards fed a monitor. This arrangement required multiple slots in a computer chassis, and it required complex wiring. Moreover, it was complex and difficult to control the array of cards in order to present the desired programming in the desired way on the desired monitors.
By contrast to this conventional approach, adapters according to the present invention each can contain the accelerator and TV out functionality to support multiple monitors. For example, adapters according to the present invention can feature 4 TV Out interfaces to support four television monitors. (They can also accept external television signals for display on one or multiple television monitors.) Four adapters each of which supports 4 monitors can occupy slots in a single computer to support an array of 4 by 4 (16) television monitors, thereby creating an impressive video wall. This represents considerable cost saving over previous methods of single video cards with single TV out cards, greatly reducing cabling and number of bus slots and cards needed in a computer. Not only is space saved in the computer and complex wiring issues avoided, but this arrangement according to the present invention allows the adapter cards to be controlled from one interface supported by the computer in order to control what programming goes on what TV monitor in the desired way.
According to a preferred embodiment of the present invention, a TV Out signal can be generated to accommodate composite, S-Video or any other desired standards, present or future. Any other desired signals can be supplied to connectors on the adapter to be coupled to one or more television monitors. Multiple output standards including NTSC-M, NTSC-44, PAL-B, PAL-G, PAL-H, PAL-I, PAL-M, PAL-N, PAL60, SECAM, and S-VHS can be supported. The TV out signals can be in addition to computer video output so that either or both television or computer monitors may be supported.
Each TV Out connection can have the same capability of its associate monitor. Therefore computer data or video decoder data from television tuners or outside signals can be displayed on the television. This provides the television sets with full function video wall capability allowing for display of one or multiple pieces of visual content or programming, whether computer or television tuner originated. Each piece of content or program can appear on an individual monitor or multiple monitors. Alternatively, multiple content can appear, some on individual monitors, some on multiple. The monitors can include television monitors, computer monitors, or a mixture of both, or any desired sort of monitor or viewing or rendering device or interface, whether cathode ray tube, liquid crystal display, or other.
Adapters according to the present invention can include one or more video inputs to feed one or more on-board television tuners which can accept external television signals from an outside source, such as a cable television company or a video cassette recorder. As an alternative, adapters of the present invention can accept television programming from external or other television tuners. As a further alternative, no information or programming from any television tuner need be accepted, processed or displayed; in this case, adapters according to the present invention feed monitors, including multiple television monitors, and optionally but not necessarily with the ability also to feed one or more computer monitors, with programming generated by computer rather than television tuning circuits.
Objects and advantages of the invention will be apparent in part in the description preceding and which follows together with the drawings, and in part will be apparent from the description or may be learned by practice of the invention.